[PATCH v2] iio: adc: stm32: fix null pointer on defer_probe error

[Ahmad Fatoum]

On 22.11.21 15:38, Olivier Moysan wrote:
> dev_err_probe() calls __device_set_deferred_probe_reason()
> on -EPROBE_DEFER error. If device pointer to driver core
> private structure is not initialized, an null pointer error occurs.
> This pointer is set on iio_device_register() call for iio device.
> 
> dev_err_probe() must be called with the device which is probing.
> Replace iio device by its parent device.
> 
> Fixes: 0e346b2cfa85 ("iio: adc: stm32-adc: add vrefint calibration support")
> 
> Signed-off-by: Olivier Moysan <olivier.moysan at foss.st.com>

Reviewed-by: Ahmad Fatoum <a.fatoum at pengutronix.de>

> ---
> Changes in v2:
> - Use parent device from indio_dev instead of private structure
> ---
>  drivers/iio/adc/stm32-adc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c
> index 7f1fb36c747c..341afdd342cc 100644
> --- a/drivers/iio/adc/stm32-adc.c
> +++ b/drivers/iio/adc/stm32-adc.c
> @@ -1986,7 +1986,7 @@ static int stm32_adc_populate_int_ch(struct iio_dev *indio_dev, const char *ch_n
>  			/* Get calibration data for vrefint channel */
>  			ret = nvmem_cell_read_u16(&indio_dev->dev, "vrefint", &vrefint);
>  			if (ret && ret != -ENOENT) {
> -				return dev_err_probe(&indio_dev->dev, ret,
> +				return dev_err_probe(indio_dev->dev.parent, ret,
>  						     "nvmem access error\n");
>  			}
>  			if (ret == -ENOENT)
> 


-- 
Pengutronix e.K.                           |                             |
Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |